provide inject

用于解决父辈向孙祖孙辈传递参数 1.父组件引入provide

import { provide, ref } from "vue";

const data = ref(false);
provide("flag", data);

2.孙祖孙被接收

import { inject, ref } from "vue";
let data = inject("flag", ref(false));
const changeData = () => {
  data.value = !data.value;
};

Inject第二个参数为兜底逻辑，若传值不符合规范则执行兜底逻辑，可传一个值，也可传一个方法